功 能:与1CAM-l(CD54)、ICAM-2(CDl02)、ICAM-3(C1350)结合,介导细胞黏附;与JAMl结合,参与白细胞穿过内皮细胞
CD11
CD11a, b and c all have same beta chain (CD18)
Members of integrin receptor family; heterodimers of noncovalently associated alpha and beta subunits
CD11a
Aka alpha L; LFA-1 (in complex with CD18)
An alpha integrin chain that binds to CD18 and mediates leukocyte adhesion and lymphocyte recirculation through lymph nodes
With CD18, binds to ICAM-1 (CD54, leukocyte adhesion molecule) and ICAM-2 (CD102)
Facilitates lymphocyte blastogenesis, cellular cytotoxicity, lymphocyte-endothelial cell adhesion, and binding to unopsonized bacteria (E. coli) and fungi (Hislasma capsulatum)
Note: patients with leukocyte adhesion deficiency (mutations in CD18) have often fatal immunodeficiency early in life
Marker of differentiation in acute promyelocytic leukemia
Positive staining (normal): all leukocytes
Negative staining: platelets
CD11b
Aka CR3, iC3b receptor
Mediates phagocytosis of particles opsonized with iC3b
Facilitates neutrophil aggregation, adhesion to substrates by opsonization, chemotaxis
Ligands include fibrinogen, Factor X, ICAM-1, Saccharomyces cerevisiae, Staphylococcus epidermidis, Hislasma capsulatum,
Note: C3 is common to classical and alternate complement pathway, and serves as an amplification step
C3b (activated C3) can amplify by cleaving more C3 via the alternate complement pathway
Positive staining (normal): follicular dendritic cells, granulocytes, macrophages, myeloid cells beginning with promyelocytes, NK cells, some B/T cells
Positive staining (disease): AML-M1-M3 (35-70%), M4-M5 (80-90%); hairy cell leukemia (virtually all)
CD11c
Aka CR4, iC3b receptor
Clears opsonized particles and immune complexes; also binds to fibrinogen and is involved in adhesion of monocytes and neutrophils to endothelium
Member of beta 2 family of integrin receptors
Prognostic value: associated with good prognosis in
B-CLL
Positive staining (normal): 50% of activated CD4/CD8+ T cells; granulocytes, lymphocytes, macrophages, NK cells
Positive staining (disease): AML-M4-M5 (50%); hairy cell leukemia (virtually all), B-CLL